[vidarh]

The problem is now you're reinventing the entire software stack of everyone you ever need to communicate with about it.

Consider how hard it is to even get people to use additional symbols, like the APL's do...

[skybrian]

Yes, good example. On the other hand, emojis seem pretty popular, and many programming languages do support non-ascii symbols in identifiers. We just don’t use them much for actual code.

Along with markdown, there’s also increasing support for math equations in forums and blogging software.

[vidarh]

Emojis have universal appeal. Coding symbols doesn't.

Math symbols are a better example, but also extremely well established, and it's still taken a very long time to get widespread support, and it's still far from universal.

But note that non-ASCII symbols etc. was an example of the difficulty of even getting support for something "that simple". Now try to take the step up to e.g a node-based editor.